Try this "counting numbers to 100":

<a href="http://www.youtube.com/v/VbHBYGY2fs0&rel=1" target="_blank">http://www.youtube.com/v/VbHBYGY2fs0&rel=1</a>

 

It's great! Thanks Brillkids

It's ok to buy a digital piano for lower grade.  The cons of digital piano is that the dynamics are not controllable, and it affects the learner's expression. Moreover, as the pieces becomes more difficult and the musical notes have to be played faster, I found digital piano produce good enough sound.

Hope it helps.